Heel mold



C. 2. NEDDEN 5 Sheets-Sheet 1 HEEL MOLD Filed Oct. 10, 1966 t R f D A "T Inventor:

Nov. 12, 1968 c. z. NEDDEN 3,409,943

HEEL MOLD Filed Oct. 10, 1966 5 Sheets-Sheet 2 Inventor: [lag] I Nov. 12, 1968 c. z. NEDDEN 3,409,943

HEEL MOLD Filed Oct. 10, 1,966 5 Sheets-Sheet 5 Fig. 5 A i Fig. 6 h }1-72 15 Fig. 7 15 v g w Inventor:

6/44 21.1- Wald! United States Patent 3,409,943 HEEL MOLD Claus zur Nedden, Westerhausen, Kreis Melle, Germany, assignor to Firma Westland-Gummiwerke G.m.b.H. & C0., Westerhausen, Kreis Melle, Germany Filed Oct. 10, 1966, Ser. No. 585,403 Claims. (Cl. 18-42) The present invention relates to a mold, and more particularly to a mold having a composite mold cavity. Still more specifically, the invention relates to a mold wherein a composite mold cavity is provided in such a manner that diverse materials can be subjected to a preliminary treatment in individual portions of the mold cavity and that subsequently such materials can be subjected to a joint treatment in the composite mold cavity constituted by the individual portions.

In the molding of articles from various materials, and partiouiarly in the molding of rubber or composition heels in which the main portion or body of the heel consists of one material and a relatively thin layer is applied to the underface of the heel and consists of a different material, which may for instance be more resistant to abrasion than the main portion, it is essential that the main portion and the thin plate, hereafter respectively referred to as the heel body and the heel plate, be simultaneously manufactured. This is dictated by reasons of economy since it is uneconomical to manufacture the heel body and the heel plate separately and subsequently to join them, for instance by means of adhesives. This requires additional labor steps and unnecessarily raises the manufacturing cost of the completed heel. It should be noted, however, that although it has been above-stated that if it is essential that the heel body and the heel plate be manufactured simultaneously, the industry as a Whole still utilizes individual heel plates and heel bodies which are subsequently joined.

It is therefore a general object of my invention to overcome the disadvantages set forth above with respect to the prior art.

A more specific object of the invention is to provide a mold in which the heel body and the heel plate can be simultaneously manufactured.

An additional object of the invention is to provide a mold of the general character just outlined in which the heel body and the heel plate, consisting of different materials can be separately pretreated and can subsequently be subjected to a joint treatment in which they are no longer separated and during which they are integrally united.

A further object of the invention is to provide such a mold which is simple and inexpensive to manufacture, and reliable in its operation.

In accordance with the objects set forth above, and with others which will become apparent hereafter, a mold according to my invention is provided particularly for subjecting diverse materials simultaneously and individually to a preliminary treatment in separate mold cavities and for subsequently subjecting such materials to a simultaneous joint treatment in a composite mold cavity. Such a mold comprises a first and a second mold section each of which has a surface juxtaposed with the corresponding surface of the other, and each of the surfaces is provided with a recess. The mold sections are movable between a spaced position in which these surfaces are spaced from each other and in which the recesses constitute separate cavities, and an abutting position in which the surfaces abut against each other and the recesses together constitute the composite mold cavity. I further provide separator means having opposed faces and being slidably movable between a first location in which it is interposed between the mold sections when the same are in their spaced position and in which the faces of the separator means abut the respective surfaces and define with the recesses provided in these surfaces the above-mentioned separate mold cavities, and further being slidably movable to a second location in which the separator means is withdrawn from between these mold sections so that the latter may be moved to the aforementioned abutting position in which the surfaces abut each other and the recesses communicate and together define the composite mold cavity.

The novel features which are considered as characteristics for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of SPC! cific embodiments when read in connection with the ac companying drawings, in which:

FIG. 1 is a longitudinal section through a mold em bodying my invention;

FIG. 2 is a top-plan view of the separator means used in the mold according to FIG. 1;

FIG. 3 is a side-elevational view, partly broken away and sectioned, of the mold of FIG. 1 with the mold sections in spaced position and the separator means being in the first location;

FIG. 4 is a view similar to FIG. 1, but 'with the separator means removed from between the mold sections and the latter being in abutting position;

FIG. 5 is a top-plan view of a further embodiment of the separator means; and

FIGS. 6-10 are transverse sections through a separator means similar to that shown in FIG. 5, but provided on its surfaces on one or more of its surfaces with wario-us different types of depressions and/ or projections.

Discussing now the drawing in detail, and firstly FIG. 1 thereof, it will be seen that I therein show a lower mold section 1 which is provided with a recess 2 of desired configuration, in the exemplary embodiment having the shape of the heel plate. The lower mold section 1 is further provided with one or more depressions or bores 3 which accept guide pins or projections 4 provided on an intermediate mold section 5 which overlies the lower mold section 1. The intermediate mold section 5 is provided with a recess 10 corresponding, in the embodiment shown by way of example, to the configuration of the heel body. One or more biasing means, such as the springs 9, are arranged intermediate the mold sections 1 and 5 and tend to bias the same apart to the spaced position mentioned earlier. It is to be noted that the mold sections 1 and 5 are provided with suitable depressions which must be of such depth that the springs 9, when compressed by movement of the mold sections 1 and 5 into abutting engagement, are wholly received within these recesses and do not constitute an obstacle to abutting engagement of the mold sections 1 and 5. There is further provided an upper mold section 6 which in effect constitutes a lid and which overlies the intermediate mold section 5. Cooperating guide bores 7 and guide pins 8 are provided in the mold sections 5 and 6, respectively, for guiding and locating the sections relative to one another. It will be understood that the mold section 6, when removed from the intermediate mold section 5 in the manner of a lid, permits free access to the recess 10 of the mold section 5 to thereby permit removal of molded articles from this recess and, since the latter communicates under certain circumstances and as Will be described more fully below, with the recess 2 of mold section 1 and forms therewith a composite cavity, the removal also of such articles from the recess 2. Mold section 6 is provided, as is evident from the drawing, with a downwardly projecting portion 11, the so-called stamp, which projects into the recess 10 when the mold section 6 overlies the intermediate mold section and which assures that a depression of desired configuration is molded 'into the' article being manufactured in the composite mold cavity consisting of the recesses 2 and 10.

In accordance with the invention there is further provided a substantially plate-shaped separator means 12 which is shown in more detail in FIG. 2. As is evident there this separator means is in effect a plate-shaped element and it is clear from FIG. 1 that this element has an upper and a lower face. v

If, now, the element 12 is introduced between the lower mold section 1 and the intermediate mold section 5 with its faces in abutment with the respective surfaces of these sections in which the recesses 2 and are provided, then the upper and lower faces of element 12 will define with the surrounding wall portions of the lower mold section 1 on the one hand, and of the intermediate mold section 5 and the upper mold section 6 on the other hand, two individual cavities 2, 10. Of course, it will be obvious that the arrangement of the novel mold must be such that the guide pins 4 and the springs 9 do not prevent such introduction of the element 12 between the mold sections 1 and 5.

Once the faces of the element 12 define with the remaining mold sections the individual cavities 2, 10, the diverse materials can be introduced into these cavities, for instance a harder material into the cavity 10 and a softer material into the cavity 2, vice versa. Means for introducing the materials into these cavities are well known and need be neither shown or described. It should be pointed out, however, that it is also possible to first fill the cavity 2, subsequently to introduce the separator means 12 between the section 1 and the section 5, thereupon to fill the cavity 10 and only then to place the upper mold section 6 on top of the intermediate mold section 5. This has no bearing on the present invention and is mentioned here only in order to clarify completely how the material can be introduced into the separate cavities 2, 10. Once this is done, the materials in the mold simultaneously, but in their individual cavities 2, 10 undergo a preliminary treatment, for instance a pre-vulcanizing treatment. During this treatment the materials are partially vulcanized and thereafter the mold sections 1 and 5 are slightly moved apart to permit withdrawal of the separator means 12 from between these sections. In accordance with the invention it is not necessary to move the sections 1 and 5 apart to any great degree, and once a slight movement has taken place the separator means 12 can be quickly and reliably removed from between the sections 1 and 5. This is important because it is desirable to avoid free and easy access of the ambient atmosphere to the hot material in the individual mold cavities 2 and 10, it being well known that such access 'with the resulting cooling of the material adversely affects the quality of the molded materials.

FIG. 3 shows the mold of FIG. 1 in operative condition for the pre-vulcanizing procedure and the two different types of vulcanizable material are clearly discernible in the respective mold cavities 2, 10.

Immediately upon withdrawal of the separator element 12 the mold sections 1 and 2 are moved into abutment with one another, as is shown in FIG. 4. Now the individual mold cavities 2, 10 are in direct communication with one another and together define a composite mold cavity which in its configuration corresponds to the shape of the completed heel consisting of the heel body which is located in the cavity portion 10and the heel plate located in the cavity portion 2. Depending upon the characteristics of the vulcanizable materials in the mold portions 2, 10 it may be desirable to heat the mold during the vulcanizing stage shown in FIG. 4, as it is indeed heated during the preliminary vulcanizing stage shown in FIG. 3. Means for heating the mold for this purpose are well known to those skilled in the art and it is not believed necessary to show such means or to describe them in detail. It is also well known that at the end of the preliminary vulcanizing stage the materials which are undergoing vulcanization retain a certain natural tackiness, that is adhesive ability. As a result of this adhesive ability the heel body located in the mold portion 10 and the heel plate located in the mold portion 2, which now are in contact with one another sincethe mold portions 2 and 10 together nowdefine the composite mold cavity, are integrally united during the final vulcanizing step which takes place with the mold sections 1 and 5 in the position shown in FIG. 4;

Merely for the sake of completeness it should be pointed out that it is of course possible to add separate adhesive means to the exposed surfaces of 'the' heel body and heel plate located in the separate mold cavities 2, '10 after the separator element 12 has been withdrawn and before the mold sections 1 and 5 are moved into abutment so that the individual mold cavities 2, 10 together define the composite mold cavity;

It is furthermore possible to enhance the strength of the bond between the heel plate and the heel body still further by providing the separator element 12 with recesses and projections in accordance with a further concept of the present invention. This is shown in FIGS. 5- 10. FIG. 5 shows that the separator element 12 is provided with a plurality of transversely extending grooves 15 between which there are of course located upwardly projecting strips. It will be obvious that complementary recesses and projections will be formed during the vulcanization in either the heel body, the heel plate or both depending on whether the recesses 15 are provided on one or on both sides of the separator element 12. When the latter is subsequently removed from between the mold sections 1 and 5 the projecting portions of one or both heel membersthat is the heel body and/or the heel pl atewill press against the respective other member with a force which is somewhat greater than would otherwise be the case. During the final vulcanization this results in a stronger bond than would be obtained without these recesses and projections.

FIG. 6 is a section taken on the line AB of FIG. 5 and indicates that in the embodiment of FIGS. 5 and 6 the recesses and corresponding projections are provided only on one side of the separator element 12.

FIG. 7 indicates a different embodiment in which the recesses 15 do not extend over the entire width of the separator element 12 and that their end portions 16 terminate inwardly of the edge faces of the separator element.

FIG. 8 shows yet a further embodiment of the separator means. The modification shown in this figure is selfevident and need not be specifically described.

The embodiment of FIG. 9 differs from those of FIGS. 58 in that both the upper and the lower side of the separator element 12 are provided with alternating recesses and projections which in configuration correspond to those shown in FIG. 8. The reference numerals applied are again the same as in the preceding figures. Advantageously, each recess on one side of the separator element 12 is backed on the other side not by a projection, but also by a recess, and the same is true of the projections which are so arranged that each projection on one side is backed by a projection on the other side. The reason for this is that the converse arrangement would not provide the additional desired pressure of the heel members against one another which with the inventive embodiments results when the mold is in the position shown in FIG. 4.

FIG. 10, finally, shows an embodiment of the separator element 12 in which both faces of the separator element 12 are provided with a depression 15a which may extend only over part of the surface area of each face, such part corresponding to that surface area which is to be juxtaposed with the respective individual mold cavity 2, 10, or which may also extend over the entire surface area. Naturally, this depression 15a can also be provided on only one of the faces of the separator element 12 if this is desired. It is to be noted, however, that with the embodiment of FIG. the opposed surfaces of the mold sections 1 and 5 must be slightly convex so that the pressure which results at the center of the mold when the mold sections 1 and 5 are placed into abutment with one another exceeds somewhat the pressure nearer to the edges of the mold sections.

Returning briefly to the embodiment in FIG. 1 it should be pointed out that the mold sections 1 and 5 can be provided with grooves or channels 13, 14 located adjacent the respective recesses 2, 10 and adapted to accept overflowing material, for instance during the vulcanizing process. However, the provision of the grooves or channels 13, 14 is not a necessity.

It will be understood that a particular advantage of the mold in accordance with the present invention is the fact that the separator element 12 can be rapidly withdrawn between the mold sections 1 and 5 with only insignificant loss of heat from the mold so that the vulcanizable material in the cavities 2, 10 is not cooled to an extent which could adversely influence its quality. Furthermore, with the mold in accordance with the present invention the heel body and the heel plate are joined precisely to one another so that there is no trace of the aesthetically displeasing overhanging of one part over the other which is so frequently found in heels or similar members constructed under prior-art procedures.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of molds differing from the types described above.

While the invention has been illustrated and described as embodied in a mold, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. A mold, particularly for subjecting diverse materials simultaneously and individually to a preliminary treatment in separate mold cavities and for subsequently subjecting such materials to a simultaneous joint treatment in a composite mold cavity, comprising a first and a second mold section having respective juxtaposed surfaces each provided with a recess, said mold sections being movable between a spaced position in which said surfaces are spaced from each other and said recesses constitute separate cavities, and an abutting position in which said surfaces abut against each other and said recesses together constitute a composite cavity; and separator means having opposed faces and being slidably movable between a first location in which it is interposed between said mold sections when the same are in said spaced position and in which said faces abut the respective surfaces and define with the respective recesses said separate mold cavities, and second location in which said separator means is withdrawn from between said mold sections so that the latter may be moved to said abutting position in which said surfaces abut each other and recesses communicate and together define said composite mold cavity.

2. A mold as defined in claim 1, wherein said separator means is a plate-shaped element.

3. A mold as defined in claim 1; and further comprising biasing means tending to permanently bias said mold sections to said spaced position thereof.

4. A mold as defined in claim 1; and further comprising overflow means associated with the respective recess for accommodating material overflowing therefrom.

5. A mold as defined in claim 4, wherein said overflow means comprises at least one groove provided adjacent to and in communication with the respective recess.

6. A, mold as defined in claim 2, wherein said plateshaped element is provided on at least one of said faces thereof with at least one surface portion extending to one side of the general plane of the respective face.

7. A mold as defined in claim 2, wherein said plateshaped element is provided on said opposite faces thereof with a plurality of projections and depressions, the projections and depressions on one face being located directly oppositely the projections and depressions, respectively, on the other face.

8. A mold as defined in claim 6, wherein said surface portion extends over at least that area of the respective face which in said first location of the plate-shaped element is juxtaposed with the respective recess.

9. A mold as defined in claim 2, wherein said plateshaped element comprises an edge face extending from one to the other of said opposed faces, and wherein at least one of said opposed faces is provided with a plurality of projections and depressions all located inwardly of the junction of said one opposed face and said edge face.

10. A mold as defined in claim 1, wherein one of said mold sections in provided with a further surface substantially parallel with the opposed surface of said one mold sections and located at the side of the mold sections which faces away from said opposed surface, the recess in said opposed surface extending to said further surface; and wherein said mold further comprises an additional mold section adapted to overlie said further surface and cover said recess.

References Cited UNITED STATES PATENTS 1,673,505 6/1928 Haase. 2,133,788 10/1938 Olakley. 2,203,543 6/1940 Pancorbo. 2,232,216 2/1941 Daly. 3,320,687 5/1967 Leveque.

J. HOWARD FLINT, JR., Primary Examiner. 

1. A MOLD, PARTICULARLY FOR SUBJECTING DIVERSE MATERIALS SIMULTANEOUSLY AND INDIVIDUALLY TO A PRELIMINARY TREATMENT IN SEPARATE MOLD CAVITIES AND FOR SUBSEQUENTLY SUBJECTING SUCH MATERIALS TO A SIMULTANEOUS JOINT TREATMENT IN A COMPOSITE MOLD CAVITY, COMPRISING A FIRST AND A SECOND MOLD SECTION HAVING RESPECTIVE JUXTAPOSED SURFACES EACH PROVIDED WITH A RECESS, SAID MOLD SECTIONS BEING MOVABLE BETWEEN A SPACED POSITION IN WHICH SAID SURFACES ARE SPACED FROM EACH OTHER AND SAID RECESSES CONSTITUTE SEPARATE CAVITIES, AND AN ABUTTING POSITION IN WHICH SAID SUFACES ABUT AGAINST EACH OTHER AND SAID RECESSES TOGETHER CONSTITUTE A COMPOSITE CAVITY; AND SEPARATOR MEANS HAVING OPPOSED FACES AND BEING SLIDABLY MOVABLE BETWEEN A FIRST LOCATION IN WHICH IT IS INTERPOSED BETWEEN SAID MOLD SECTIONS WHEN THE SAME ARE IN SAID SPACED POSITION AND IN WHICH SAID FACES ABUT THE RESPECTIVE SURFACES AND DEFINE WITH THE RESPECTIVE RECESSES SAID SEPARATE MOLD CAVITIES, AND SECOND LOCATION IN WHICH SAID SEPARATOR MEANS IS WITHDRAWN FROM BETWEEN SAID MOLD SECTIONS SO THAT THE LATTER MAY BE MOVED TO SAID ABUTTING POSITION IN WHICH SAID SURFACES ABUT EACH OTHER AND RECESSES COMMUNICATE AND TOGETHER DEFINE SAID COMPOSITE MOLD CAVITY. 